"Today, Poppy Orpington is hardly remembered at all."
The above first line in Full Throttle is (of course) designed to hook the reader; who was Poppy, and why has she been forgotten? But we may also ask who is telling us about Poppy? Who is addressing us so directly?
The in-universe answer is a contemporary editor, James Birkin, telling Poppy’s story to clear her name of allegations of treason in war-time Europe. But the real reason? It appears from online reviews and editorial feedback that the “third person omniscient” narrator is falling out of fashion. In its place is the “third person limited”, which is limiting indeed as the narrator cannot know anything the characters don’t know.
Hence this set-up, in which Birkin is drawing on personal diaries, letters, news reports etc to reconstruct Poppy’s life and times, and thus he does (thankfully) know more than the characters do.
Though this approach does then raise the issue of the unreliable narrator…